Vibrator-engine.



No. 788,209. PATBNTED SEPT. 8, 1903.

W. LEWIS.

VIBRATOR ENGINE.

APPLICATION FILED AUG. 21. 1902.

N0 MODEL.

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UNITED STATES Patented September 8, 1903.

PATENT OFFICE.

WILFRED LEWIS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE TABOR MANUFACTURING COMPANY, OF PHILADELPHIA, PENNSYLVA- NIA, A CORPORATION OF NEW JERSEY.

VlBRATOR-ENGINE.

SPECIFICATION forming part of Letters Patent No. 738,209, dated September 8, 1903.

Application filed August 21,1902. Serial No. 120,607. (No model.)

To aZZ whom it may concern.-

Be it known that LWILERED LEwIs, a citizen of the United States, and a resident of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a certain new and useful Improvement in Vibrator-Engines, of which the following is a specification.

The present invention relates primarily to vibrator or rapping engines intended for use in connection with mold making apparatus for the purpose of preventing the sand from adhering to the pattern during the operation of separating the pattern from the mold. Ilcretofore owing to the method of admitting fluid-pressure to such engines these engines have had to be formed from forged metal and their pistons have been very liable to get on a dead-center unless a spring is used to keep the piston in an initial or starting position.

One object of the present invention is to provide a vibrator or rapping engine wherein the piston maybe started from all positions thereof in the cylinder.

Another object is to use rolled metal for the cylinder or barrel of such engine. I

Other objects will appear hereinafter.

To these ends the invention consists of features of construction, arrangements, and combinations of devices hereinafter described and more particularly pointed out'in the appended claims.

The invention is illustrated in the accompanying drawings, forming part hereof, in which Figure 1 is a longitudinal sectional view of an engine in which the invention is embodied. Fig. i is a similar view of another form of the engine in which the invention is embodied. Fig. is a side elevation of a piston, and Fig. & is a sectional side elevation of a modified form of the invention.

In the drawings the reference a designates a cylinder, and la piston. The cylinder or barrel (1. is circular in section and may be made from rolled metal. This barrel is reduced in diameter at one end, which reduced end is provided with screw-threads b.

The cylinder is further reduced at this same end, as at c, for a purpose to appear hereinafter. The cylinder to is bored through centrally thereof ,the bore being circular throughout, but being of different diameters in different places. Thus at the end I) c the said bore cl is of a relatively small diameter, while ate said bore is of a larger diameter, and the end f of the barrel a is screw-threaded internally on a diameter such that the piston Z can be introduced into the cylinder through the opening. (See reference g.) The bores (Z 8 form two end-to-end chambers, and the bore of the cylinder is enlarged at 7L 1' 7a to form annular grooves or spaces of greater diameter than the chamber 6, said grooves being at the ends and the central portion of the chamber e.

The reference 7 marks an air passage or vent through the wall of the cylinder at at a point in the bore 6 adjacent to the groove h, and S a similar passage or escape at the groove 70, while 9 designates a guard secured to the cylinder to and protecting the openings 7 S against accidental closure. The blast from the opening 7 spreads both ways therefrom, and part thereof is drawn into the opening 8 as the piston is driven forward by the constant pressure, as hereinafter set forth, and the guard prevents sand or dirt from being drawn into the opening 8.

The piston 1 comprises a cylindrical end 'm, which fits into the chamber (Z, and cylindrical parts n 0, which fit into the chamber 9. A groove p, extending around the piston, separates the parts a 0, and q designates a reduced end of the piston outside of the part a. The piston in Figs. 1, 2, and 3 is bored longitudinally at 7' s, and these bores are intersected, respectively, by the cross perforations u t, the hole to opening through the part 0 adjacent to the groove 1) and the hole t openingin said groove 1), as shown.

In the form shown in Fig. l the end I) c of the cylinder a is closed by a screw-cap w, which has a threaded opening for a pipe-tap 2. A felt or other absorbent lubricant-holder a; is held on the end of the part c by the cap w, and said cap has an opening y therein for the introduction of lubricant to the said holder 0;. A screw closes the opening y tightly. The

lubricant passes from the felt ring 00 between the cap '10 (or 3 in Fig. 2) and the end of the part c to the end of the chamber d and thence to the piston to lubricate the same. The end 5 f of the cylinder a is closed by a screw-pl u g on the block 3, which engages with the threads g. The block 3 is provided with jaws 4 and a bolt and nut 5 for attaching the engine to some part of a molding apparatus, as a pattern support or carrier or vibrator-frame.

In the form shown in Fig. 2 the end f of the cylinder dis closed by a screw-plug 10 and the end I) c is closed by a screw-cap 3 which is provided with jaws i and screw-bolt 5 for attaching the engine to some part of the molding apparatus, as the flange of a frame 6. In this form of the invention the passage y and screw 5 are on the plug 3 and said plug has a passage 10, into which an elbow-pipe tap 2 screws, and the felt washer x is held in place by the plug 3 The tap 2 should point away from the molding apparatus.

In the modified arrangement shown at Fig. etthe air is admitted through a pipe-tap 2 into the annular space and passes by channels 1' u to the annular space 1' and thence through channels If s to the larger pressure area (end) of the piston The exhaust is at 7, and when the pressure is cut off by the covering of the opening a the exhaust 7 is uncovered by the part it, whereupon the unbalanced pressure on the relatively smaller annular pressure area of the part 0 throws the piston from right to left, as will be explained hereinafter.

The operation of the above-described apparatus is as follows: lVith the piston in the position shown the air on admission under pressure through pipe 2 or 2 passes through the channel r it into the annular space i. Thence it passes through the channel '6 s to the larger pressure area (end) of the piston. Since the end g has a greater area than the end m or the annular end of the part 0, the excess pressure moves the piston toward the right in Figs. 1 and at and toward the left in Fig. 2 until the end of the part 0 strikes the end of the chamber 6, by which time the part n will have uncovered the port 7 and the holes a will have been closed by passing beyond the space 2, thus exhausting at the end q, but not elsewhere. Thereupon the pressure on the end m or the annular end of part 0 forces the piston back to the position thereof shown in the drawings, and the cycle begins again, the end q striking against the plug closing the cylinder end. The passage 8 permits of the escape of any air that may leak into the space It and allows the piston to draw in and expel air without undue resistance. The

clamp 4 5 gives a firm and rigid grip upon the part to which the engine may be attached, and the rapid blows delivered by the piston cause an agitation of the sand such as prevents the adhesion thereof to the pattern.

For a better understanding of the action of engines of the class to which this invention relates reference is made to Letters Patent of the United States Nos. 533,401 and 654,292, dated, respectively, January 29, 1895, and July 24, 1900.

It is noted that the air-pressure is introd uced through the piston from its smaller end or from a smaller pressure area to the annular space at the central portion of the chamber e and that the piston by its endwise motion acts as a valve for controlling the admission to the larger end or pressure area thereof. There is thus always an unbalanced pressure in one or the other direction on the piston, whence it follows that there is no position from which it will not be moved on turning on the pressure at the smaller end or pressure area, (annulan) It is noted also that the piston can be made to strike a blow at one end only of its stroke, being cushioned by the air at the other end of its stroke. Thus the piston can be made single-acting, as stated, by removing or omitting the end q, the other parts of the piston and cylinder being unchanged, or by removing or omitting a portion of the part 0, as that portion thereof to the right of the line 1 1 in Fig. 3, as by turning down that portion of part 0 to the size of the neck 11, the other parts of the piston and cylinder remaining as shown in the drawings, or by continuing the bore 6 beyond the groove 70 in Figs. 1 and 2.

iVhat is claimed as new is 1. The combination of a closed cylinder having therein two end-to-end chambers of unequal diameters and annular spaces at and intermediate the ends of the larger chamber, said spaces being of greater diameter than said larger chamber, a plunger-piston fitting in said chambers and having a circumferential groove in the larger part thereof, a channel connecting said groove with the larger end of the piston, a channel connecting the smallenpressure area of the piston with the outside of the larger partof said piston near said groove, and pressure inlet and exhaust openings in said closed cylinder, substantially as described.

2. The combination of a closed cylinder having therein two end-to-end chambers of unequal diameters and annular spaces at and intermediate the ends of the larger chamber, said spaces being of greater diameter than said larger chamber, a plunger-piston fitting in said chambers, and means, including channels in said piston, for maintaining continuous pressure on the smaller pressure area and for varying the pressure upon the larger pressure area of said piston, substantially as described.

3. The combination of a barrel or cylinder having a reduced end, a cap for closing said end, there being an annular space between the barrel end and thecap and also a like space surrounding the barrel end, an absorbent for lubricant in the last-mentioned space, a plunger-piston in said barrel,and a pressureadmission port in said cap, substantially as described.

4. The combination of a closed cylinder having therein two end-to-end chambers of unequal diameters, a plunger-piston fitting in said chambers, means including channels in said piston for maintaining continuous pressure on the smaller end and for varying the pressure upon the larger end of said piston, a recess communicating with one of said chambers and with the source of pressure, and a lubricant-absorbent in said recess, substantially as described.

5. The combination of a closed cylinder having therein two end-to-end chambers of unequal diameters, a plunger-piston fitting in said chambers and having pressure areas of unequal sizes, and ainpassages including annular passages in said cylinder and said piston for maintaining continuous pressure upon the smaller pressure area and for varying the pressure upon the larger pressure area of said piston, substantially as described.

6. The combination of a closed cylinder having therein end-to-end chambers of unequal diameters, a plunger-piston fitting in said chambers, means for causing said piston to reciprocate under the action of air-pressure, an exhaust-opening in said cylinder for said pressure, a vent for preventing undue resistance to the motion of said piston, and an openended guard covering both exhaust and Vent and providing a space wherein the air is drawn in and expelled, substantially as described.

Signed at Philadelphia, in the county of Philadelphia and State of Pennsylvania, this 19th day of August, A. D. 1902.

lVILFRED LEWIS.

\Vitnes ses FRANCIS P. MALONE, E. II. MUMFORD. 

